Abstract: A kind of reference symbol is designed for downlink based on pilot of broadband wireless communication systems in this paper. The new pilot is made of PN code, orthogonal variable spreading factor（OVSF） code and generalized chirp like/constant amplitude zero auto-correlation(GCL/CAZAC) sequence. Simulation results indicate that the proposed method can restrain the co-channel interference in adjacent sectors and cells. The bit error rate (BER), block error rate (BLER), and throughput of the system are all improved effectively.

Key words: generalized chirp like/constant amplitude zero auto-correlation(GCL/CAZAC）, multiinput multioutput（MIMO）, orthogonal frequency division multiplexing（OFDM）
, scrambling code, reference symbol